Renesas Electronics Introduces 16- and 32-Megabit Advanced Low Power
SRAMs With Over 500 Times the Resistance to Soft Errors Compared to Full
CMOS Memory Cells

Contributes to Longer Backup Battery Service Life Reducing Standby
Current by Half

July 22, 2015 08:00 AM Eastern Time

SANTA CLARA, Calif.--(EON: Enhanced Online News)--Renesas Electronics Corporation (TSE:6723), a premier supplier of
advanced semiconductor solutions, today announced the release of two new
series of Advanced Low Power SRAM (Advanced LP SRAM), the leading type
of low-power-consumption SRAM, designed to provide enhanced reliability
and longer backup battery life for applications such as factory
automation (FA), industrial equipment, and the smart grid. Fabricated
using the 110-nanometer (nm) process, the new RMLV1616A Series of
16-megabit (Mb) devices and the RMWV3216A Series of 32 Mb devices
feature an innovative memory cell technology that dramatically improves
reliability and contributes to longer battery operation.

The recent demands for highly secure and reliable user systems are
driving increased demand for highly reliable SRAM, which is used to
store important information such as system programs and financial
transaction data. The prevention of soft errors (Note 1) caused by alpha
rays and cosmic neutron rays is a significant issue. Typical measures to
deal with this problem include embedding an error correcting code (ECC)
circuit in the SRAM or user system to correct any soft errors that
occur. There are limits, however, to the error correction capabilities
of ECC circuits. For example, some cannot correct simultaneous errors
affecting multiple bits.

Renesas’ Advanced LP SRAM devices feature exclusive technology in their
memory cells that achieves soft error resistance (Note 2) over 500 times
that of conventional Full CMOS memory cells (Note 3). This makes it
desirable for use in fields requiring high reliability, including FA,
measurement devices, smart grid-related devices, and industrial
equipment, in addition to many other fields, such as consumer devices,
office equipment, and communication devices.

In the Renesas Advanced LP SRAM structure, a stacked capacitor (Note 4)
is added to each memory node (Note 5) within the memory cells. This
configuration suppresses the generation of soft errors to a level that
is effectively soft error free (Note 6). In addition, the load
transistor (P-channel) of each SRAM cell is a polysilicon thin-film
transistor (TFT) (Note 7) that is stacked on top of the N-channel MOS
transistor formed on the silicon. Only the N-channel MOS transistor is
formed on the silicon substrate below. This means that no parasitic
thyristors are formed in the memory area and theoretically makes
latch-up (Note 8) impossible. Therefore, the Advanced LP SRAM is well
suited to applications requiring high reliability, such as FA,
measurement devices, smart grid related devices, traffic systems, and
industrial equipment.

(2) Reduction of standby current to less than
half the earlier level for longer backup battery service life

The standby current of the new RMLV1616A Series and RMWV3216A Series is
only 0.5 microamperes (μA) (typical) for 16 Mb devices and 1 μA
(typical) for 32 Mb devices (Note 9). These low current consumption
levels are less than half the levels of comparable earlier Renesas SRAM
products (Note 10), making it possible to extend the service life of
backup batteries. The minimum power supply voltage when retaining data
is 1.5 V, lower than the 2.0 V of comparable earlier Renesas products.
This helps customers designing systems that retain data using battery
power.

(3) Package lineup

The 16 Mb RMLV1616A Series is available in three packages: 48-ball FBGA,
48-pin TSOP (I), and 52-pin μTSOP (II), allowing customers to select the
package that best matches their application. The 32 Mb RMWV3216A Series
is available in a 48-ball FBGA package.

Refer to the separate sheet for the main specifications of the new
RMLV1616A Series and RMWV3216A Series.

Pricing and Availability

Samples of the RMLV1616A Series and RMWV3216A Series will be available
in September. Pricing varies depending on capacity. For example, the 16
Mb RMLV1616A Series is priced at US$16.50 per unit, and the 32 Mb
RMWV3216A Series at US$31 per unit. Mass production of the two series is
scheduled to begin in October 2015. Mass production using the 110 nm
process has already begun for Advanced LP SRAM products with 4 Mbit and
8 Mbit capacities.

(Note 1) Soft errors:A phenomenon that occurs when alpha rays and
cosmic neutron rays from external sources impinge on the silicon
substrate, generating an electric charge within the substrate that
causes information stored in the memory to be lost. In contrast to hard
errors such as physical faults in the semiconductor elements, which are
reproducible, soft errors are not reproducible, so the system can
restore the original state simply by rewriting the data. Generally
speaking, the rate of soft errors increases as the fabrication process
becomes more ultrafine.

(Note 2) Based on system soft error evaluations performed by Renesas.

(Note 3) Full CMOS memory cells:A SRAM memory cell configuration
in which a total of six P-channel MOS transistor and N-channel MOS
transistor elements are formed on the same plane of the silicon
substrate. The surface area is large and there is a latch-up risk.

(Note 4) Stacked capacitor:Capacitors with two electrodes formed
from polysilicon or metal. These capacitors are formed on the upper
layer of the MOS transistors on the silicon substrate.

(Note 6) Renesas has published on its website the results of its
evaluations of soft errors in systems employing Advanced LP SRAM. These
evaluations were run for more than a year under conditions similar to
the usage environment of average users, and in the end no errors were
detected. See the following URL for details:http://www.renesas.com/products/memory/low_power_sram/child/renesas_effort.jsp

(Note 7) Thin-film transistor (TFT):A transistor formed from
thin-film polysilicon. Such elements are used as the SRAM load
transistors, formed on the top layer of the MOS transistors on the
silicon substrate.

(Note 8) Latch-up:A phenomenon in which an NPN or PNP structure
(parasitic bipolar transistor) formed by the well, silicon substrate,
P-type diffusion layer, and N-type diffusion layer of a CMOS transistor
enters the on state due to overvoltage from the power supply or input
pins, allowing a large current to flow between the power supply and
ground.

(Note 9) Reference values at a power supply voltage of 3.0 V and ambient
temperature of 25°C.

(Note 10) The R1LV1616R Series and R1WV3216R Series, which employ the
150 nm process.

About Renesas Electronics Corporation

Renesas Electronics Corporation (TSE: 6723), the world’s number one
supplier of microcontrollers, is a premier supplier of advanced
semiconductor solutions including microcontrollers, SoC solutions and a
broad-range of analog and power devices. Business operations began as
Renesas Electronics in April 2010 through the integration of NEC
Electronics Corporation (TSE:6723) and Renesas Technology Corp., with
operations spanning research, development, design and manufacturing for
a wide range of applications. Headquartered in Japan, Renesas
Electronics has subsidiaries in 20 countries worldwide. More information
can be found at www.renesas.com.

(Remarks) All registered trademarks or trademarks are the property of
their respective owners.

Separate Sheet

Main Specifications of RMLV1616A Series
and RMWV3216A Series

(16- and 32-Megabit Devices Using the 110
nm Process)

Power supply voltage: 2.7 V to 3.6 V

Minimum voltage when retaining data: 1.5 V

Product No.

Capacity

Word Organization

Package

Access Time

Standby Current

Sample Price

Sample Shipment

RMLV1616AGBG-5S2

16 Mb

×16

FBGA (48)

55 ns

Up to 25°C:

0.5 μA (typ.)

3μA (max.)

Up to 40°C:

0.8 μA (typ.)

6 μA (max.)

Up to 70°C:

2.5 μA (typ.)

12 μA (max.)

Up to 85°C:

5 μA (typ.)

16 μA (max.)

US$

16.50

Sep. 2015

RMLV1616AGSA-5S2

TSOP I (48)

Jan. 2016

RMLV1616AGSD-5S2

μTSOP II (52)

Sep. 2015

RMWV3216AGBG-5S2

32 Mb

FBGA (48)

Up to 25°C:

1μA (typ.)

6μA (max.)

Up to 40°C:

1.6 μA (typ.)

12 μA (max.)

Up to 70°C:

5 μA (typ.)

24 μA (max.)

Up to 85°C:

10 μA (typ.)

32 μA (max.)

US$31

Sep. 2015

(Remarks) All names of products or services mentioned in this
press release are trademarks or registered trademarks of their
respective owners.